BigFoot Mobility Device End Tip

ABSTRACT

A pseudo-frustoconical shaped unitary rubber end unit for an ambulatory device, such as a cane, comprising, a bottom hexagonal base and a top circular rim, wherein said base is about four times the diameter of said rim and functions to provide significantly enhanced support and stability; and a central cylindrical “socket” created by six deeply recessed side walls and a resultant six member rib-like frame that functions to optimize device&#39;s shock absorption capabilities and forward propulsion of the user. The hexagonal base may be asymmetrical or symmetrical, and the ribs may be of uniform or non-uniform dimensions. The hexagonal base and the rib-like frame act synergistically to compress and rebound under loads creating a twisting “spring assist” action that both absorbs shock and helps propel users forward. The broad base has a slightly recessed underside permitting the mobility device to be self-standing.

PRIORITY CLAIMS TO RELATED PROVISIONAL APPLICATIONS

The present application claims priority benefit to U.S. ProvisionalPatent Application Ser. No. 61/343,129, filed Apr. 23, 2010 by MichaelE. Adams, entitled “6 sided substantially conical elastomeric broad baseshock absorbing floor tip for canes and crutches”, the disclosure ofwhich is incorporated by reference.

TECHNICAL FIELD OF THE INVENTION

This invention relates generally to tips and bases for canes and relatedambulatory aids, and more specifically to those tips and bases havingboth sufficient size so as to markedly improve the support and stabilityof such devices, and an overall construction specifically designed toactively assist a user moving through a gait cycle.

BACKGROUND OF THE INVENTION

Tips or bases of different sizes and configurations have long beenfitted to the bottom end of canes and other ambulatory aids. To agreater or lesser degree, each is designed to absorb shock, increasesupport and stability, and improve the traction of the associateddevice. The traditional tip is a simple molded rubber piece press fittedonto the lower shaft of a cane or crutch. Typically conical in shape, ittapers from a narrow upper collar to a bottom rim approximately twicethe shaft diameter, and features a concave underside with concentricrubber rings that contact the ground as the tip compresses. Whilepreferable to a blunt wood or metal shaft, these tips contribute littleto improving user comfort, safety or convenience. One of the mostwell-known conical tips is the “Tornado” Tip (U.S. Pat. No. 4,881,564)by Thomas Fetterman, Inc. Top quality materials and a resilient “corestructure” between the bottom rim and the main body, and a “pivotingmid-section” combine to improve both shock absorption and traction.Improvements in overall support are marginal, however, and thecombination of expensive materials and a sophisticated construction arereflected in its premium price.

So called “quad” bases have long been the most popular alternative toconical tips. Rectangular plates with downward pointing, rubber tippedtubes at each corner, they are best known for providing improvedstability when held at a user's side, and for making a caneself-standing when it is not in use. For all these benefits, however,quad bases offer just intermittent support, and are typically comprisedof several cumbersome and heavy steel parts. Additionally, large gapsbetween the tubular legs, and the ease with which those legs can snag orcatch on any number of surfaces, make quad bases a real trip hazard. TheQuadruple Cane Tip by Sky MedSupply International Corporation shows fourcontact points configured in a cross-rather than arectangular-orientation. While this does make a device self-standing,the deep voids between the “tip arms” still present a trip hazard, andthe north/south/east/west orientation of the contact points is even moreproblematic than a typical quad base in terms of abrupt, “on again-offagain” support.

A newer alternative is the “Able Tripod” cane tip marketed by LA CareIndustries, LLC. Three ground contacting lobes flare out from a centralmolded body with the forward facing lobe containing a strip of springsteel. The broad “footprint” made by the three lobes combines with theresilience of the spring to improve support and stability, while alsoactively assisting a user as they move through a gait cycle. However,the effectiveness of the spring-biased lobe in response to loads ishighly variable, and the large voids between the lobes provide nosupport to stabilize the user throughout their gait.

In addition to the tip and base styles outlined above, variousmanufacturers offer spring-biased conical tips, “articulated body”conical tips, rigid “tri” (three tip) bases, spring mounted quad bases,flexible molded plastic quad bases, and other variations on thesethemes. To date, however, no known device has been of sufficient size,configuration and construction to offer greatly enhanced support andstability, omnidirectional shock absorption and spring assist, an“unbroken” bottom rim, a self-standing feature, improved traction, and alow cost to manufacture all in a single product. Accordingly, there is aneed within the art of tips for the ends mobility devices that providesupport to a standing and walking user that offers these enhancedfeatures: makes devices self-standing, increases support and stabilityfor the user, optimizes shock absorption and floor traction; andactively assists users moving through a gait cycle by generating a“spring-like” forward propulsive force.

SUMMARY OF THE INVENTION

The present invention is a new type floor tip for canes and crutchesthat employs a novel, resilient shape to reconcile desirable functionsand features of numerous competing designs in a single, simple device.More specifically, the present invention is a unitary molded rubberdevice that combines a squat, hybrid, main body-spring element with ashallow, ground contacting pad element, to increase user support,stability and safety, make an associated ambulatory aid self-standing,improve traction, absorb shock, and actively assist a user movingthrough a gait cycle.

The present invention is directed to an improved tip for a mobilitydevice, wherein the device is used to provide support to a standing userthroughout their gait, such as a cane or crutch. The design of thepresent invention comprises a unitary molded rubber device ofessentially a conical shape with a bottom hexagonal base and a topcircumferential collar, otherwise known herein as a“pseudo-frustoconical shape”. Furthermore, it comprises: a hexagonalconcave floor engaging base; six side walls with deeply recessed panelssurrounded by a rib-like frame; and a top rim encircling a cylindricalcavity. This cavity houses the mobility device cane or crutchcylindrical tube, and thus is also known as the “central tube receivingsocket”. The mobility device's cylindrical vertical tube, such as thatfound in canes or crutches, is press fitted to the tip of the presentinvention within the central tube receiving socket.

The hexagonal base of the present invention is significantly wider indiameter as compared to the prior art, thus altering the dimensions andthe functionality of the components of the end piece. The base isbetween about 100 and 130 millimeters in diameter; the “rib-like” framelies at about a 40-50 degree angle above the horizontal plane; and in apreferred embodiment is about 45 degrees. The associated recessed panelsare of about 37 to 41 millimeters in height; and the ribs of about 7 to11 millimeters in thickness. This structural alteration providesenhanced levels of compressibility, otherwise known as shock absorption,and stability of the mobile device, while also providing a novelmechanism to affect forward propulsion of the user.

In a further embodiment of the present invention, the ribs framing themobility device tip are of two different sizes to enhance shockabsorption, stability, and the forward propulsion of the user. From anoverhead, cross-sectional view of the tip for forward motion, the tworibs in the tip front 1100 and 100 (at 11 and 1 o'clock) and the tworibs in the tip rear 500 and 700 (at 5 and 7 o'clock) are thicker thanthe two ribs on the tip sides 300 and 900 (at 3 and 9 o'clock). Thefront and rear ribs are also slightly longer than the side ribs.Furthermore, the width of each rib may be uniform or not. All six ribspossess a wider end connecting with the bottom floor hexagonal base ascompared to remainder of their rib length. The wider, terminal end ofeach rib at the floor engaging base improves stability, while thethinner mid-section of the ribs provides enhanced compressive andrebound forces and flexibility in the tip as a whole, while alsoproviding a variably manifested “spring-like” force to assist inpropelling the user forward.

In another aspect of the present invention, the bottom floor engagingbase is hexagonal in shape, and concave in a downwardly facing surfacedirection, and with a plurality of alternating rubber rings andrecesses. Additionally, the perimeter, and tallest protrusion ring isquickly angled vertically from its outer rim towards the tip center suchthat the only point-of-contact of the mobility device with the floorwhen the device is in a vertical, unloaded position is the outer rim ofthe perimeter ring. This is for the purpose of minimizing the tractionforce that must be overcome when lifting the mobility device off thefloor, while optimizing the traction and compressive forces when themobility device is supporting the user's weight. As either vertical oroblique compressive forces are applied to the mobility device by theuser, the perimeter protrusion ring laterally expands and flattensdownward such that the entire diameter of the ring ultimately comes incontact with the floor. The plurality of alternating rubber rings andrecesses provide enhanced traction and compression by permitting thefloor engaging rings (e.g. protrusion rings) to laterally expand andthus maximize contact with the floor when under compressive loads.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention and its different aspects and advantages will be betterunderstood from the following detailed description of preferredembodiments of the invention with reference to the following drawing:

FIG. 1 is an elevated perspective view of the end piece or tip of thepresent invention.

FIG. 2 is an overhead view of the present invention.

FIG. 3 is a side, cross-sectional view of the present invention.

FIG. 4 is an underneath view of the bottom end piece of the presentinvention.

FIGS. 5A-C are illustrations of snapshots in time through the gait of auser employing the present invention on his/her right side. FIG. 5Aillustrates the end piece at the moment the device is placed in front ofthe user; FIG. 5B illustrates the end piece as the user is essentiallyparallel to and leaning vertically onto the device; and FIG. 5Cillustrates the end piece as the user is completing his stride and theinvention is unloading.

DETAILED DESCRIPTION OF THE INVENTION

Previously, the prior art of the inventor of the present inventiondisclosed and claimed a mobility device comprising a hexagonal end tipas shown in U.S. Pat. No. 7,610,926 issued Nov. 3, 2009 entitled“Mobility Device”, the entirety of which is incorporated by reference.In particular, FIGS. 13-18 of U.S. Pat. No. 7,610,926 disclosed apseudo-frustoconical shape with six facets or side walls 62. Each sidewall 62 includes a depressed panel 64 surrounded by an outstandingrib-like frame 66, wherein the depressed panels are of a few millimetersin depth such that the side walls are almost vertical. The presentinvention is based on an unexpected discovery that a user of a mobilitydevice experiences much increased stability, compressibility andmeasureable spring assistance to their ambulation when the end piece isre-modeled by dramatically increasing the depth of the depressed panelsso as to make the resultant, circumferential ribs much more prominent.Additionally, a novel springing, or propulsive force is generated toassist the user in forward motion by the variably deflecting, twistingand rebounding action of the front, rear and side ribs. The springingaction is further refined by the variable width of the front and rearversus the side ribs, and by modifying the individual ribs along theirlength such that they are thicker at the floor base than in the middle.For the purpose of the present invention, the term “about” is defined as+/−5%.

The floor engaging end piece 58, or otherwise known alternatively hereinas tip, of the mobility device of the present invention comprises afrustum or pseudo-frustoconical shape, such that its basic shape isconical, but with the top tip removed so as to form a plane essentiallyparallel to the base. As shown in FIG. 1, the top plane is comprised ofan outer circular rim 20 about 4 to 7 millimeters thick and about 22 to32 millimeters in diameter (as measured from the outer rim) with aninner cavity, otherwise known as a central tube receiving socket 30 ofabout 1.25 inches to 1.75 inches, or 31.75 millimeters to 44.45millimeters in depth. In a preferred embodiment as illustrated in FIG.1, the central tube receiving socket 30 has a depth of about 1.5 inches,or 38.1 millimeters deep. As shown in FIG. 3, end piece 58 is pressfitted (defined as the process by which the friction between two partsis sufficient to securely join them together) to the lower portion of amobility device 14, which is preferably formed from one-piece hollowmetallic tubing such as aluminum and most preferably “aircraft grade”aluminum. End piece 58 may be made of rubber, or a resilient rubber-likeplastics material. Preferably, end piece 58 is made from a moldedelastomeric material which is solid in composition and semi-rigid instructure. In a preferred embodiment of the present invention, a flatsupport disc, preferably metal, may reside between the base of thecavity of the end piece and the metallic tubing 14, as illustrated inFIG. 3, item 40. The disc may comprise preferably about 1.5 to 2.5millimeters in thickness and functions to prevent erosion of the endpiece cavity bottom surface from various load forces exerted by themetallic tubing 14.

As illustrated in FIGS. 1 and 2, end piece 58 preferably has apseudo-frustoconical shape with six facets or side walls wherein eachside wall includes a vertical standing rectangular-like depressed panel64 adjoined to an approximately horizontal standing trapezoidal-likeramp 68 surrounded by a rib-like frame 66. The depressed panels 64 areabout 90 degrees to the horizontal trapezoidal-like ramps 68, while therib-like frame lies about 40 to 50 degrees from a horizontal position.In a preferred embodiment, the rib-like frame lies at about a 45 degreeangle from the horizontal. The end piece 58 height may range from about2.0 inches to 2.5 inches; and the end piece floor engaging base mayrange from about 4.0 inches to 5.0 inches in diameter. The actualdimensions of each end piece 58 model is a function of the overall sizeof the mobility device for which it is designed. In a preferredembodiment, the end piece height is about 2.15 inches or 54.6millimeters; and the floor engaging hexagonal base is about 4.5 inchesor 114 millimeters in diameter.

The rib-like frame of the present invention furthermore comprises, asillustrated in FIG. 1, six flexible “ribs” 66 extending from the top,outer rim 20 of the central tube receiving socket 30 to one each of thesix points of the hexagonal base 72. The six ribs are separated by thesix adjacent, deeply recessed pockets, comprising the horizontaltrapezoids 68 residing at about 90 degrees angle to the essentiallyvertical rectangular-like panels 64. The ribs 66 may be of uniform sizeor not. In a preferred embodiment as exemplified in FIG. 2 and as viewedoverhead from the perspective of FIGS. 5A-C, the front ribs 1100 and 100(at 11 and 1 o'clock in forward motion) and the rear ribs 500 and 700(at 5 and 7 o'clock) are thicker than side ribs 300 and 900 (at 3 and 9o'clock). Additionally, each rib may be of uniform thickness along itslength or not. In the preferred embodiment, the width of front and rearribs are thicker at the hexagonal base than in the rib midsection forthe purpose of providing more compressibility and thus comfort to theuser throughout their gait.

As can be seen in FIGS. 3 and 4, for example, the bottom of end piece 58is concave downward towards the floor wherein only the outer rim ofperimeter ring 72 makes contact with the floor in an unloaded state asshown in the side view of end piece 58 in FIG. 3 A view of the bottom,floor engaging part of end piece 58 shows that it is hexagonal in shapeand is comprised of two non-touching six-sided rings 72 and 70encircling a solid center pad 80, wherein the rings are prevented fromcontacting each other via recesses 84 and 86. It is an essential featureof the present invention that the rings are not touching so as toprovide space for the rings to compress, laterally expand and maximizecontact with the floor for optimal compression, stability and thenrebound throughout a user's gait and range of motion. In a preferredembodiment of the present invention, the perimeter ring 72 possesses aninward angle of about 45 degrees such that only its outer rim contactsthe floor in an unloaded state, and due also to the fact that the bottomring 70 and the bottom center pad 80 are of less height than theperimeter protrusion ring 72. The outer rim of perimeter ring 72provides enough traction with the floor for the mobility device to beself-standing.

BIOMECHANICAL OVERVIEW: As force is applied during a complete stride bythe user of the mobility device attached to the present invention, thedifferent portions of the end point 58 deform and progressivelycooperate in a manner to maximize the shock absorption and stabilityafforded the user, as well as the type and degree of rebounding gaitassistance provided. FIGS. 5A-C are illustrations of snapshots in timethrough the gait of a right-handed user employing the present inventionfor the purpose of substantially demonstrating the various “spring-like”actions performed by the novel structural elements of the presentinvention in response to the shifting loads it undergoes during thecourse of one complete stride. As shown in these figures, the recessedpanels, rib-like frame and broad, compliant hexagonal base of the endpiece cooperate with each other, variably deflecting and rebounding in aseamless fashion to provide substantial levels of support, stability andgait assistance.

FIG. 5A illustrates the present invention at the moment the device isplaced in front of the right handed user at the beginning of a stride.The front of the hexagonal base is in an unloaded state, while the“left, inside rear” of the base (from an overhead perspective) issubjected to compressive loads, primarily inwardly deflecting the rib700 (at the 7 o'clock), and beginning to compress or flatten theunderside of the bottom of the hexagonal base.

FIG. 5B illustrates the tip as the user is essentially parallel to, andleaning vertically onto the device. In this figure the axial compressiveloads are maximized and principally absorbed by the inward deflectiontowards the ground and slight clockwise bowing (as viewed overhead) ofthe rib 900 (at 9 o'clock), and, to a lesser extent, inward deflectionand slight bowing in the counter-clockwise direction of rib 700 (at the7 o'clock). Additionally, the maximum compression and expansion ofbottom rings 72 and 70 occurs during this phase of the gait (See FIG. 3)such that the bottom hexagonal base is significantly depressed from ribs700 to 900 to 1100.

And FIG. 5C illustrates the tip as the user is about to lift the deviceoff the ground. At this point in the stride, the innermost rib 900 (at 9o'clock) is slightly bowed to the rear (e.g., counterclockwise), and thefront inner rib 1100 (at 11 o'clock) is partially deflected inward, andthen-along with rib 900-rebounds to its original shape as the device islifted off the ground, cooperating with the rebounding/unloading forcegenerated by the hexagonal base to help propel the user forward.

The foregoing description and the accompanying drawings are illustrativeof the present invention. Still other variations in arrangements ororientations of parts are possible without departing from the spirit andscope of this invention.

1. A floor-engaging end piece of a mobility device for providingambulatory support for a user, of essentially a pseudo-frustoconicalshape comprising, a unitary rubber unit with a central cylindrical“socket” created by six deeply recessed side walls and a resultant sixmember rib-like frame, wherein said frame functions to propel a userthrough each phase of their gate while optimizing said device's shockabsorption capabilities.
 2. The end piece of claim 1, wherein saidrib-like frame comprises six evenly spaced ribs lying at about 40 to 50degrees from the horizontal plane.
 3. The end piece of claim 2, whereinat least two of said six ribs are wider at the bottom base to provideadditional stability.
 4. The end piece of claim 2, wherein at least twoof said ribs are thinner in the mid-section than on the ends to provideadditional shock absorption and forward propulsion of said user.
 5. Theend piece of claim 2, further comprising a bottom hexagonal base and atop circular rim, wherein said base is about four times the diameter ofsaid rim and functions to provide significantly enhanced user stability,and to permit said device to be self-standing.
 6. The end piece of claim2 wherein said circular rim and said central cylindrical “socket”encompass a cylindrical cavity for housing the lower end of a mobilitydevice.
 7. The end piece of claim 6, wherein said lower end of amobility device is a cylindrical metal tube of a cane or crutch pressfitted into said cylindrical cavity.
 8. The end piece of claim 5,wherein said hexagonal base further comprises a hexagonal shapedunderside surface with a plurality of rings and recesses wherein saidrings expand under compression to increase traction of said device tothe floor.
 9. The end piece of claim 8, wherein the rim of the outerring of said plurality of rings is the only of point of contact of saiddevice with the floor in a non-compression state and functions tominimize traction of said hexagonal underside surface to the floor whenlifting said mobility device.
 10. The end piece of claim 8, wherein saidhexagonal underside has a concave downwardly facing surface when viewedfrom overhead.
 11. A floor-engaging end piece of a mobility device forproviding ambulatory support for a user, of essentially apseudo-frustoconical shape comprising, a unitary rubber unit with acentral cylindrical “socket” created by six deeply recessed side wallsand a resultant six member rib-like frame that functions to propel auser through each phase of their gate while optimizing said device'sshock absorption capabilities; and an asymmetrical bottom hexagonalbase.
 12. The end piece of claim 11, wherein said six member rib-likeframe lies about 40 to 50 degrees from the horizontal plane, and furthercomprises two front and two rear ribs longer and thicker than the twoside ribs to provide additional stability and shock absorption.
 13. Theend piece of claim 11, wherein at least two of said six ribs are widerat the bottom base to provide additional stability.
 14. The end piece ofclaim 11, wherein at least two of said ribs are thinner in themid-section than on the ends to provide additional shock absorption andforward propulsion of said user.
 15. The end piece of claim 11, furthercomprising a bottom hexagonal base and a top circular rim, wherein saidbase is about four times the diameter of said rim and functions toprovide significantly enhanced user stability and to permit said deviceto be self-standing.
 16. The end piece of claim 11, wherein saidasymmetrical hexagonal base further comprises an asymmetrical hexagonalshaped underside surface with a plurality of rings and recesses whereinsaid rings expand under compression to increase traction of said deviceto the floor surface.
 17. The end piece of claim 16, wherein the rim ofthe outer ring of said plurality of rings is the only point of contactof said device with the floor in a non-compression state to minimizetraction when lifting said mobility device.
 18. The end piece of claim16, wherein said asymmetrical hexagonal shaped underside has a concavedownwardly facing surface when viewed from overhead.
 19. The end pieceof claim 16, wherein said asymmetrical hexagonal shaped undersidesurface maintains continuous contact with the floor throughout a stride.